docs: def sample_folder(prj, sample):
      """
      Get the path to this Project's root folder for the given Sample.
  
      :param attmap.PathExAttMap | Project prj: project with which sample is associated
      :param Mapping sample: Sample or sample data for which to get root output
          folder path.
      :return str: this Project's root folder for the given Sample
      """
      return os.path.join(prj.metadata.results_subdir,
                          sample["sample_name"])